The nine current TPP members have been discussing the countries' applications since.

Ultimately, that is a decision for both Malaysia and the current TPP countries, he said.

The nine current TPP countries will hold their 13th round of talks in early July in San Diego, California.

A final decision to allow Japan into the negotiations would have to be made by all the current TPP members.

But all the current TPP countries agree "that we really, really want this to be a fast-moving process," he said.